This makes ^W behave more like zsh: deleting either a path component or the
word. This is rather convenient. We must use stty erase undef first as there
exists a binding, and thus the binding does not take effect.

149 is a weird width and less useful when given some thought. Using a vertial
split to see two files simultaneously requires 160+ columns. We end up with a
lot of whitespace that is slightly annoying. Just resize to 89 columns, which
gives us a bit of wiggle room (numbers, context, colour column, etc).